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Biomedical subjects

H Ostertag

Publications and source records attributed to H Ostertag.

At least 73 records · Page 4Linked to original sources
PubMed1985

11C-butanol for imaging of the blood-flow distribution in tumor-bearing animals.

1-11C-n-Butanol produced semiautomatically using a cyclotron was employed to investigate the whole-body distribution and kinetics of the label of this compound. Following the administration of 11C-butanol into the aorta of two dogs, more than 80% of the activity was cleared from the blood within 1 min. The activity distribution mirrored the cardiac output distribution as determined using 121I microspheres. Within 25 min p.i., a significant release of decay-corrected activity was only observed for the liver, spleen, and kidneys. Muscle and whole-body activity showed constant levels during this period. In 45 tumor transplants from rats, the dynamic behavior of the label was studied. The tissue retention of activity following injection into the a. femoralis was approximately 100% during the 1st 15 s for both tumor and muscle (n = 6). The activity release by tumors during the 1st 10 min after intra-aortic injection was 18% +/- 4.5% (n = 39; decay corrected). In five different tumor lines (n = 10), the initial 11C-butanol uptake was related to that of muscle, and the results were correlated with the tumor-to-muscle retention of 121I-microspheres (r = 0.89). In 17 tumors, the correlation between 11C-butanol uptake and the washout rate of 133Xe resulted in a correlation coefficient of 0.96. Tumor-to-muscle uptake ratios could be equally determined using intra-aortic and intravenous injection, as evaluated by intraindividual comparison in 12 rats (y = 0.01 + 0.98x; r = 0.98). 11C-Butanol appears to be an appropriate radiotracer for the assessment of blood supply to malignant tumors relative to muscle.

1-Butanol↗
PubMed1985

Selective drug-induced reduction of blood flow in tumor transplants.

The effect of a calcium antagonist and a physiologic amine on tumor and muscle perfusion was investigated with the aim of improving the preconditions for external hyperthermia treatment of cancer. Nisoldipine (0.04-4.0 mg/kg) and 5-hydroxy tryptamine (5-HT) (0.2-8.0 mg/kg) were administered i.p. in Sprague-Dawley rats bearing Walker 256 carcinoma, Yoshida sarcoma, or a homologous tumor transplant derived from a spontaneous leiomyosarcoma of the uterus. At the maximum dosage used, nisoldipine injection caused a decrease of the regional washout rate of Xenon-133 of 63 +/- 8% (SEM) in the Walker carcinoma and an increase of 80 +/- 41% in the muscle of the hind leg. 5-HT (8 mg/kg) caused a drop of 79 +/- 29% in the Walker carcinoma and only a slight fall of the washout rate in muscle of 14 +/- 4.8%. Tumor-to-muscle uptake ratios of 11C-butanol fell from 5.63 +/- 1.98 to 3.32 +/- 1.21, and from 5.3 +/- 0.56 to 2.98 +/- 0.30, after injection of 0.2 mg/kg nisoldipine and 4 mg/kg 5-HT, respectively. Similar reaction patterns and percentage changes were observed in different tumor lines at constant doses of 0.2 mg/kg nisoldipine and 4 mg/kg 5-HT. Both drugs representing two different rationales of vasomotor action were able to reduce blood flow specifically in transplanted tumors; nisoldipine increased muscle blood flow and decreased arterial blood pressure, whereas 5-HT acted without substantial systemic effects.

Animals↗
PubMed1984

Ameloblastic fibro-odontome. Report of a case, with ultrastructural study.

An ameloblastic fibro-odontome of the mandible in an 11-year-old female is reported. The clinical, radiological, histological and electron microscopic findings are presented and compared to similar cases reported in the literature. Histogenetic features as well as differential diagnostic aspects of the ameloblastic fibro-odontome are discussed.

Cell Nucleus↗
PubMed1984

[Ossifying fibroma of the bone].

In the spectrum of the fibroosseous bone tumours the ossifying fibroma of the bone (OF) is situated as a not yet clearly defined entity with many names. The present paper deals with the question wether a term innovation brings elucidation to clinical management. Therefore 811 previously published and 16 additional cases have been analysed with respect to their clinical and radiological behavior. In addition a simplificated histological reclassification was performed on 284 well documented literature cases. It was found that there are no great differences between these tumours according to their localisation, their clinical behavior, and their prognosis. All tumours of this group are suitable to different categories of histological maturation of the same tumour best called "ossifying fibroma".

Adolescent↗
PubMed1984

N-13 L-glutamate uptake in malignancy: its relationship to blood flow.

Studies on glutamate uptake, with special reference to perfusion, were carried out in 35 rats, each bearing one of five different tumor transplants; also in 15 rats after bone fracture, and in three rabbits. Single-pass extraction of N-13 glutamate was 85-93% in the VX2 tumor of the rabbit and in muscle. Bone fracture in rats caused a threefold increase of tracer uptake 2 days after the event. In tumor transplants, the tumor-to-muscle uptake ratio reached a maximum immediately following injection of the tracer. Comparing N-13 glutamate uptake with the retention of 1-121 microspheres, identical tumor-to-muscle ratios were found for three out of five tumor lines. Comparing the uptake with that of C-11 butanol (ten rats), a close correlation was observed throughout the range of tumor lines. The results suggested that glutamate uptake by malignant tumors is related to blood flow. In nine patients with malignant or benign lesions tumor-to-muscle uptake of N-13 glutamate and TI-201 showed a linear correlation close to identity.

Adolescent↗
PubMed1982

Uptake and turnover of L-(13N)-glutamate in the normal human heart and in patients with coronary artery disease.

L-(13N)-glutamate (4-8 mCi) was administered IV to 27 patients with coronary artery disease and to 12 control subjects. Quantitative whole body imaging of the 13N label was performed in 31 individuals at different time intervals following the injection. Initial uptake of the total myocardium was estimated to be 5.0 +/- 0.88% of the dose. Standardized areas of reduced size on the projection plane contained 2.38 +2- 0.41% of the total dose in control subjects and 2.67 +/- 0.49% in coronary patients. Subsequent imaging exhibited significant differences in the dynamic behavior of both groups: 13N activity loss within 10 min was 3.2 +/- 4.2% of the initial value in control subjects and 16.0 +/- 9.8% in coronary patients. In individual cases a high myocardial accumulation of the 13N label was observed in regions of reduced 201Tl uptake. The findings are explained by an augmented extraction efficiency in cases of flow reduction. Glutamate utilization may be involved in metabolic adaptations of the myocardium to chronic or repetitive ischemia and may be worthy of further investigation by positron emission tomography.

Adolescent↗
PubMed1982

Radioisotope therapy of cystic craniopharyngomas.

Eighteen patients suffering from cystic craniopharyngeoma were treated with intracavitary irradiation. The beta-emitting radioisotope 90y (2.25 MeV) was instilled into the cyst following stereotactic puncture of the space-occupying lesion. The surgical approach was planned using angiograms and reconstructed transmission computer tomography (TCT) coronal and saggital sections. Therapy was devised to deliver 20,000 rad to the cyst's wall. Eleven patients received follow-up TCT examinations after four months. Eight of 11 patients had a significant volume decrease in the craniopharyngeoma cyst. In two patients, the cystic volume remained unchanged; one had progression of disease. It is concluded that the intracavitary treatment of cystic craniopharyngeoma will result in a reduction of the size of the space-occupying lesion.

Adolescent↗
PubMed1982

[X-ray manifestation of early gastric carcinoma (author's transl)].

Evaluation of x-ray films of 44 early carcinomas of the stomach in a total of 163 patients from 1970--1978 confirms the high diagnostic value of x-ray examination with adequate technique. In 93% of the cases lesions caused by the carcinoma were seen. To assess the severity of the roentgenologically detected lesions it will be necessary to perform endoscopic-bioptical examination. Final diagnosis, however, must be left to histological examination of the resected stomach preparations.

Humans↗
PubMed1981

[General hypothermia. First aid and clinical treatment].

The general problematic of accidental hypothermia is pointed out. 12 patients have been treated with a new procedure of rewarming. This method is easy to apply, both at the site of accident and in the clinic without any risks. Considering the important principle of rewarming the core ("core fist") our method is successfully applied with only a few means.

Accidents↗
PubMed1981

[Fibrous metaphyseal defect (fibrous cortical defect, non-ossifying fibroma). Paper II: differential diagnosis (author's transl)].

FMD, whether in the stage of a fibrous cortical defect or a non-ossifying fibroma, possesses very characteristic radiological appearances which rarely make it necessary to resort to biopsy. In order to avoid mistakes, it is necessary to observe strictly the known radiological features: metaphyseal position, clearcut relationships to the cortex, well defined margins, maximal size 6 to 7 cm., presence during growth, rarely observed in the upper extremity. The differential diagnosis, which needs to be considered only rarely, is discussed.

Adolescent↗
PubMed1981

[Malignant fibrous histiocytoma of bone (MFH)--an new tumour? ].

Malignant fibrous histiocytoma of bone (MFH) is a histologically defined bone tumour, which can be distinguished from osteo- and fibrosarcomas. The present paper deals with the question whether MFH can be distinguished from these tumours on clinical grounds. One hundred and fifty-seven previously published, and four additional cases have been analysed with respect to their localisation and their biological, clinical and radiological behaviour and their prognosis. It was found that MFH can be distinguished from osteosarcomas on clinical grounds and that this is significant in relation to treatment; its distinction from fibro-sarcomas is clinically not justified.

Adolescent↗
PubMed1981

[Indication and treatment with surgical therapy in primary non-epithelial cancers of the stomach].

The importance of surgical treatment in non-epithelial, primary malignant tumors of the stomach was investigated retrospectively in 27 cases. 85.2% of these tumors were non-Hodgkin lymphomas, 14.8% were leiomyosarcomas and Hodgkin's disease. There were no typical symptoms; those present resembled the symptoms of carcinomas and peptic ulcers. Most patients showed symptoms on average 6 months prior to diagnosis. Histocytological studies of endoscopic biopsies enabled a correct diagnosis to be made preoperatively in up to 75% of cases. The postoperative mortality was 14.8%; the 5-year survival rate was 56.2%. Thus the prognosis is significantly better than that of advanced cancer of the stomach.

Adult↗
PubMed1981

Rhabdomyosarcoma of the oral cavity in children: report of five cases with ultrastructural study.

Five cases of oral rhabdomyosarcoma in childhood are reported. Four of these children, who were all aged between 3 and 14 years, were girls. In all patients, combined therapy was undertaken which included tumour resection, radiation and chemotherapy. Problems in treatment and prognosis are discussed, and the clinical, histomorphological and ultrastructural findings are described.

Adolescent↗
PubMed1981

[Adenoacanthoma of the pancreas (author's transl)].

Case reports are given of 5 patients with adenoacanthoma of the pancreas. Clinical aspects of this syndrome are discussed taking into account the own cases and cases reported in the literature; there are no differences of the clinical picture as compared to pancreatic carcinoma of ductal type. Surgery of this type of malignancy does not improve life expectancy, however in many cases surgery is justified because it may alleviate pain. Only 1,1-4,4% of all patients with pancreatic carcinoma do harbour adenoacanthoma - thus further case reports may contribute to better describe the clinical and pathological picture of this disease and possibly to further elucidate the pathogenesis.

Adenocarcinoma↗